S
- Sawtooth – Power Mac G4 (AGP Graphics)
- Scimitar – Mac OS 8.1
- Shadow – Macintosh Quadra 700
- Show Biz – Macintosh Quadra 630
- Show & Tell – Macintosh Quadra 630
- Silk – Power Mac G3 (Blue & White)
- SixPack – System Software 6
- Skia – QuickDraw GX
- Slice – Macintosh Color Classic
- Smoke and Mirrors – Twentieth Anniversary Macintosh
- SnakeBite – Power Mac G4 (Gigabit Ethernet)
- Snowbird - iPhone OS 1.1, 1.1.1
- Snow Leopard – Mac OS X 10.6
- Snow Leopard – Mac OS X Server 10.6
- Son of Pismo – iBook (14.1 LCD)
- Sonata – Mac OS 9
- Spartacus – Twentieth Anniversary Macintosh
- Speedbump 610 – Macintosh Quadra 610
- Speedbump 650 – Macintosh Quadra 650
- Spike – Macintosh Quadra 700
- Spock – Macintosh IIx
- Spruce Goose – PowerBook 540/540c
- SR-71 – PowerBook 540, 540c, 550c, 500 with PowerPC
- Star Trek – Prototype of System 7.1 for x86 processors
- Stealth – Macintosh IIfx
- Stingray – Macintosh IIci
- Stratos – Macintosh IIx
- Sugar Bowl – iPhone OS 2.1, 2.1.1
- SuperMario – Toolbox ROM version $077D
Read more about this topic: List Of Apple Codenames